/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.catalina.ha.authenticator;

import org.apache.catalina.*;
import org.apache.catalina.authenticator.SingleSignOn;
import org.apache.catalina.authenticator.SingleSignOnEntry;
import org.apache.catalina.ha.CatalinaCluster;
import org.apache.catalina.ha.ClusterValve;
import org.apache.catalina.tribes.Channel;
import org.apache.catalina.tribes.tipis.AbstractReplicatedMap.MapOwner;
import org.apache.catalina.tribes.tipis.ReplicatedMap;
import org.apache.tomcat.util.ExceptionUtils;

import java.security.Principal;

/**
 * A <strong>Valve</strong> that supports a "single sign on" user experience on
 * each nodes of a cluster, where the security identity of a user who successfully
 * authenticates to one web application is propagated to other web applications and
 * to other nodes cluster in the same security domain.  For successful use, the following
 * requirements must be met:
 * <ul>
 * <li>This Valve must be configured on the Container that represents a
 * virtual host (typically an implementation of <code>Host</code>).</li>
 * <li>The <code>Realm</code> that contains the shared user and role
 * information must be configured on the same Container (or a higher
 * one), and not overridden at the web application level.</li>
 * <li>The web applications themselves must use one of the standard
 * Authenticators found in the
 * <code>org.apache.catalina.authenticator</code> package.</li>
 * </ul>
 *
 * @author Fabien Carrion
 */
public class ClusterSingleSignOn extends SingleSignOn implements ClusterValve, MapOwner {

	/**
	 * Descriptive information about this Valve implementation.
	 */
	protected static final String info =
			"org.apache.catalina.ha.authenticator.ClusterSingleSignOn";


	// -------------------------------------------------------------- Properties

	private CatalinaCluster cluster = null;
	private long rpcTimeout = 15000;
	private int mapSendOptions =
			Channel.SEND_OPTIONS_SYNCHRONIZED_ACK | Channel.SEND_OPTIONS_USE_ACK;
	private boolean terminateOnStartFailure = false;
	private long accessTimeout = 5000;

	/**
	 * Return descriptive information about this Valve implementation.
	 */
	@Override
	public String getInfo() {

		return (info);

	}

	@Override
	public CatalinaCluster getCluster() {
		return cluster;
	}

	@Override
	public void setCluster(CatalinaCluster cluster) {
		this.cluster = cluster;
	}

	public long getRpcTimeout() {
		return rpcTimeout;
	}

	public void setRpcTimeout(long rpcTimeout) {
		this.rpcTimeout = rpcTimeout;
	}

	public int getMapSendOptions() {
		return mapSendOptions;
	}

	public void setMapSendOptions(int mapSendOptions) {
		this.mapSendOptions = mapSendOptions;
	}

	public boolean getTerminateOnStartFailure() {
		return terminateOnStartFailure;
	}

	public void setTerminateOnStartFailure(boolean terminateOnStartFailure) {
		this.terminateOnStartFailure = terminateOnStartFailure;
	}

	public long getAccessTimeout() {
		return accessTimeout;
	}

	public void setAccessTimeout(long accessTimeout) {
		this.accessTimeout = accessTimeout;
	}

	// ---------------------------------------------------- SingleSignOn Methods

	@Override
	protected boolean associate(String ssoId, Session session) {
		boolean result = super.associate(ssoId, session);
		if (result) {
			((ReplicatedMap<String, SingleSignOnEntry>) cache).replicate(ssoId, true);
		}
		return result;
	}

	@Override
	protected boolean update(String ssoId, Principal principal, String authType,
	                         String username, String password) {
		boolean result = super.update(ssoId, principal, authType, username, password);
		if (result) {
			((ReplicatedMap<String, SingleSignOnEntry>) cache).replicate(ssoId, true);
		}
		return result;
	}

	@Override
	protected SessionListener getSessionListener(String ssoId) {
		return new ClusterSingleSignOnListener(ssoId);
	}


	// -------------------------------------------------------- MapOwner Methods

	@Override
	public void objectMadePrimay(Object key, Object value) {
		// NO-OP
	}


	// ------------------------------------------------------- Lifecycle Methods

	/**
	 * Start this component and implement the requirements
	 * of {@link org.apache.catalina.util.LifecycleBase#startInternal()}.
	 *
	 * @throws LifecycleException if this component detects a fatal error
	 *                            that prevents this component from being used
	 */
	@Override
	protected synchronized void startInternal() throws LifecycleException {

		// Load the cluster component, if any
		try {
			if (cluster == null) {
				Container host = getContainer();
				if (host instanceof Host) {
					if (host.getCluster() instanceof CatalinaCluster) {
						setCluster((CatalinaCluster) host.getCluster());
					}
				}
			}
			if (cluster == null) {
				throw new LifecycleException(
						"There is no Cluster for ClusterSingleSignOn");
			}

			ClassLoader[] cls = new ClassLoader[]{this.getClass().getClassLoader()};

			ReplicatedMap<String, SingleSignOnEntry> cache =
					new ReplicatedMap<String, SingleSignOnEntry>(
							this, cluster.getChannel(), rpcTimeout, cluster.getClusterName() + "-SSO-cache",
							cls, terminateOnStartFailure);
			cache.setChannelSendOptions(mapSendOptions);
			cache.setAccessTimeout(accessTimeout);
			this.cache = cache;
		} catch (Throwable t) {
			ExceptionUtils.handleThrowable(t);
			throw new LifecycleException(
					"ClusterSingleSignOn exception during clusterLoad " + t);
		}

		super.startInternal();
	}

	/**
	 * Stop this component and implement the requirements
	 * of {@link org.apache.catalina.util.LifecycleBase#stopInternal()}.
	 *
	 * @throws LifecycleException if this component detects a fatal error
	 *                            that prevents this component from being used
	 */
	@Override
	protected synchronized void stopInternal() throws LifecycleException {

		super.stopInternal();

		if (getCluster() != null) {
			((ReplicatedMap<?, ?>) cache).breakdown();
		}
	}
}
